DE102022110807A1 - ENGINE SYSTEM WITH ELECTRIFIED AIR SYSTEM COMPONENTS FOR MANAGING NOx EMISSIONS IN A WORK VEHICLE - Google Patents

Abstract

An engine system includes an engine having an intake manifold and an exhaust manifold, a turbocharger including a turbine in communication with the exhaust manifold and a compressor in communication with the intake manifold, and a governor configured to to control an exhaust gas flow through the turbine. A controller is operatively connected to the governor and is configured to monitor an engine load and an exhaust gas temperature during operation of the engine, identify prohibited engine nitrogen oxide (NOx) emission levels based on the engine load and the exhaust gas temperature, and when the prohibited engine nitrogen oxide (NOx) emissions Emission levels have been identified, modifying exhaust gas flow through the turbine to reduce energy extracted from the exhaust gas by the turbine and to reduce motive power provided to the compressor, thereby reducing intake airflow provided to the intake manifold by the compressor.

Description

The present disclosure relates to internal combustion engines, and more particularly to engine systems with electrified air system components that operate to manage emissions of nitrogen oxides (NOx).

Diesel engine systems are used to power many work vehicles and are subject to emission regulations regarding levels of nitrogen oxides (NOx) emitted during operation. Existing diesel engine systems can meet not-to-exceed (NTE) emission limits and test requirements covering a wide range of speed and load combinations commonly encountered in use; however, it is likely that future emission regulations will lower the regulated NOx limit and expand the speed and load operating range of the regulated or NTE emission limits. Existing diesel engine systems may not be able to meet these increased NOx emission restrictions, due at least in part to the manner in which the air system components in the engine system perform at low speed, light load engine operating conditions.

An engine system includes an engine having one or more piston and cylinder assemblies in communication with an intake manifold and an exhaust manifold, a turbocharger having a turbine in communication with the exhaust manifold, and a compressor driven by the turbine and in communication with the intake manifold, and a governor configured to control exhaust gas flow through the turbine. The engine system further includes a controller having a processor and memory architecture and operatively connected to the governor, the controller configured to monitor engine load and exhaust gas temperature during operation of the engine, prohibited engine nitrogen oxide (NOx) emission levels based on engine load and exhaust gas temperature at which NOx emissions are within a prohibited range, and when prohibited engine nitrogen oxide (NOx) emission levels have been identified, controlling the controller to modify exhaust gas flow through the turbine. By modifying the flow of exhaust gas through the turbine, an amount of energy extracted from the exhaust gas by the turbine is reduced and motive power provided to the compressor is reduced, thereby reducing intake airflow provided to the intake manifold by the compressor.

In another implementation, an engine system for a work vehicle includes an engine having one or more piston and cylinder assemblies communicating with an intake manifold and an exhaust manifold, a turbocharger having a turbine communicating with the exhaust manifold, and a A compressor driven by the turbine and in communication with the intake manifold, and a governor configured to control exhaust gas flow through the turbine. The engine system further includes a controller having a processor and memory architecture and operatively connected to the governor, the controller configured to monitor an engine load and an exhaust gas temperature during operation of the engine, determine whether the engine load and the exhaust gas temperature are below an engine load threshold and an exhaust gas temperature threshold, respectively, thereby indicating prohibited engine nitrogen oxide (NOx) emission levels, and when the engine load and the exhaust gas temperature are below the engine load threshold and the exhaust gas temperature threshold, control the controller to increase the exhaust gas flow through the turbine modify. By modifying the flow of exhaust gas through the turbine, an amount of energy extracted from the exhaust gas by the turbine is reduced and motive power provided to the compressor is reduced, thereby reducing intake airflow provided to the intake manifold by the compressor.

The details of one or more embodiments are set forth in the accompanying drawings and the description below. Further features and advantages emerge from the description, the drawings and the claims.

• 1 ist eine vereinfachte Seitenansicht eines beispielhaften Arbeitsfahrzeugs, bei dem Ausführungsformen der vorliegenden Offenbarung implementiert werden können;
• 2 ist ein Schemadiagramm eines beispielhaften Motorsystems mit elektrifizierten Luftsystemkomponenten zum Managen von NOx-Emissionen gemäß einer Ausführungsform;
• 3 ist ein Schemadiagramm eines beispielhaften Motorsystems mit elektrifizierten Luftsystemkomponenten zum Managen von NOx-Emissionen gemäß einer weiteren Ausführungsform;
• 4 ist ein Schemadiagramm eines beispielhaften Motorsystems mit elektrifizierten Luftsystemkomponenten zum Managen von NOx-Emissionen gemäß einer weiteren Ausführungsform;
• 5 ist ein Schemadiagramm eines beispielhaften Motorsystems mit elektrifizierten Luftsystemkomponenten zum Managen von NOx-Emissionen gemäß einer weiteren Ausführungsform;
• 6 ist ein Schemadiagramm eines beispielhaften Motorsystems mit elektrifizierten Luftsystemkomponenten zum Managen von NOx-Emissionen gemäß einer weiteren Ausführungsform; und
• 7 ist ein Ablaufdiagramm eines beispielhaften Verfahrens zum Betrieb eines Motorsystems mit elektrifizierten Luftsystemkomponenten zum Managen von NOx-Emissionen.

At least one example of the present disclosure is described below in connection with the following figures:

• 1 12 is a simplified side view of an exemplary work vehicle upon which embodiments of the present disclosure may be implemented;
• 2 12 is a schematic diagram of an example engine system with electrified air system components for managing NOx emissions, according to one embodiment;
• 3 12 is a schematic diagram of an example engine system with electrified air system components for managing NOx emissions according to another embodiment;
• 4 12 is a schematic diagram of an example engine system with electrified air systems system components for managing NOx emissions according to another embodiment;
• 5 12 is a schematic diagram of an example engine system with electrified air system components for managing NOx emissions according to another embodiment;
• 6 12 is a schematic diagram of an example engine system with electrified air system components for managing NOx emissions according to another embodiment; and
• 7 FIG. 12 is a flowchart of an example method of operating an engine system with electrified air system components to manage NOx emissions.

Like reference characters indicate like elements in the different drawings. For the sake of simplicity and clarity, descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the example and non-limiting embodiments of the invention described in the following detailed description. Furthermore, it should be understood that features or elements appearing in the accompanying figures are not necessarily drawn to scale unless otherwise indicated.

Embodiments of the present disclosure are shown in the accompanying drawing figures briefly described above. Various modifications to the exemplary embodiments can be devised by those skilled in the art without departing from the scope of the present invention as set forth in the appended claims.

Internal combustion engines and in particular diesel engines are used in many work vehicles and are operated under very different speed and load conditions. Such diesel engines are subject to emission regulations regarding acceptable levels of nitrogen oxides (NOx) emitted during operation, these regulations covering a wide range of speed and load combinations commonly encountered in use, i. H. an "NTE area". Although existing diesel engine systems can meet current emission regulations in this NTE range, future emission regulations will both lower the acceptable NOx limit and expand the NTE range where such a NOx limit is required. This means that acceptable NOx emission levels will be reduced overall, possibly by a factor of 10, and it is likely that the NTE range in which NOx emission limits are regulated will be extended to include low load, low speed engine operating conditions.

It is understood that the structure and operation of air systems in existing diesel engine systems does not allow the engine systems to meet these future NOx emission regulations over an expanded NTE range. First, the air systems on existing diesel engine systems do not recirculate enough exhaust gas (EGR) when the engine is operating below current NTE minimum speed levels to significantly reduce engine NOx emissions. This is because the pressure of the exhaust gas discharged from the engine is not sufficiently higher than the pressure of the intake air supplied to the engine to create a positive pressure differential that allows the exhaust gas to flow through the EGR system. Second, when the engine is running under current NTE minimum load levels, the air systems in existing diesel engine systems provide an air/force ratio that is higher than necessary, resulting in a low exhaust gas temperature, which in turn negatively impacts the conversion efficiency of SCR treatment (SCR - Selective Catalytic Reduction) of the exhaust gas, which would otherwise reduce NOx pollutant emissions to a minimum.

To reduce NOx emissions to a minimum over an extended NTE range and to a degree that meets future emissions regulations, an engine system is provided with electrified air system components that are selectively operable to better manage NOx emissions. Operation of the air system components can both increase EGR and improve SCR conversion efficiency, particularly during low speed and light load engine operating conditions, such that NOx emissions can be reduced over an extended NTE range.

According to embodiments, engine load and exhaust gas temperature are monitored during operation of the engine system to determine operating conditions where engine NOx emission levels may fall within a prohibited range. The engine load and exhaust gas temperature are compared to an engine load threshold and an exhaust gas temperature threshold, respectively, and if the engine load and exhaust gas temperature are below their respective thresholds, a prohibited engine NOx emission level or condition is identified. With such an identification, it will Engine system operable to selectively control exhaust gas flow through one or more turbines of a turbocharger assembly to increase exhaust gas temperature and reduce boost. That is, by modifying the flow of exhaust gas through the turbocharger turbine, the amount of energy extracted from the exhaust gas by the turbine is reduced, thereby maintaining a higher temperature of the exhaust gas and allowing for higher conversion efficiency with SCR treatment of the exhaust gas Reduction of NOx emissions is ensured. In addition, by reducing the amount of energy extracted from the exhaust gas by the turbine, the turbocharger is driven with a lower input force, thereby reducing the amount of intake air supplied to the engine. Reducing the intake air supplied to the engine lowers the air/fuel ratio in the engine, thereby reducing NOx emissions.

In one embodiment, an electrified wastegate is provided in the engine system for selectively directing exhaust gas away from the turbine. A governor is provided for controlling the operation of the wastegate and thereby selectively modifying the flow of exhaust gas to the turbine. If NOx emissions are determined to be at prohibited engine NOx emission levels, the controller may cause the wastegate to open so that exhaust gas bypasses the turbine. By causing the exhaust flow to bypass the turbine, the amount of energy extracted from the exhaust by the turbine is reduced, and NOx emission levels may also be reduced.

In another embodiment, a variable geometry (VG) turbocharger is provided in the engine system that may be configured to selectively reduce the amount of energy extracted from the exhaust gas by the turbine. A governor is provided that operates to adjust the aspect ratio of the turbine in the VG turbocharger and thereby selectively modify the flow of exhaust gas through the turbine. If NOx emissions are determined to be at prohibited engine NOx emission levels, the controller may cause the aspect ratio of the turbine to be adjusted such that the amount of energy extracted by the turbine from the exhaust gas is reduced so that the NOx -Emission values are also reduced.

In one implementation, an electrified air booster is included in the engine system that is selectively operable to boost intake air into the intake manifold when activated to provide improved transient response in the engine system. The air amp may be selectively operated based on a rate of change of engine load, and when the rate of change of engine load exceeds an associated engine load rate of change threshold, the electrified air amp is activated. The air amplifier may be provided as an e-compressor that includes a self-contained compressor and an electric machine that drives the self-contained compressor. The air intensifier may instead be provided as an electric machine that is mechanically coupled to the turbocharger to drive a shaft that couples the turbine and compressor such that the turbocharger is configured as an e-turbocharger. In both the e-compressor and the e-turbocharger, the electric machine operates to drive its associated compressor (either directly or via the turbocharger shaft) to cause the compressor to boost intake air into the intake manifold.

In another implementation, an exhaust gas recirculation (EGR) pump is included in the engine system and is selectively operable to recirculate a portion of the exhaust gas discharged from the exhaust manifold to the intake manifold. The EGR pump is operable to recirculate exhaust gas discharged from the exhaust manifold to the intake manifold even when the engine is running at low speed, thereby reducing engine-out NOx emission levels.

Example embodiments of an engine system having electrified engine components that operate to boost engine torque will now be described in connection with FIG 1-7 described according to this disclosure. As non-limiting examples, the engine system as described below is integrated into a work vehicle and includes a turbocharger assembly that includes series-connected high-pressure and low-pressure turbochargers for boosting airflow into the internal combustion engine. Notwithstanding the following examples, alternative work vehicles and engine systems having turbocharger assemblies having other designs would also benefit from electrified air system components integrated therein according to aspects of the invention. It is thus understood that aspects of the invention are not intended to be limited to only the specific embodiments described below.

According to embodiments, an engine system is disclosed that includes electrified air system components that operate to manage NOx emissions during operation of the engine system. As will be apparent to those skilled in the art from the following description, the application of the engine system is to work vehicles NOx emissions controlled genes are particularly appropriate and thus the illustrative examples discussed herein draw on such an environment to aid in understanding the invention.

Referring first to FIG 1 A work vehicle 10 is shown on which embodiments of the invention may be implemented. In the illustrated example, work vehicle 10 is illustrated as an agricultural tractor. However, it is understood that other configurations may be possible, including configurations in which the work vehicle 10 is another type of tractor, a harvester, a skidder, a grader, a backhoe, or any of various other types of work vehicle. The work vehicle 10 includes a chassis or frame 12 supported on front and rear wheels 14 . Positioned on a front end portion of the chassis 12 is a housing 16 in which an engine system 18 is located. The engine system 18 provides power, via an associated powertrain 20, to an output member (e.g., an output shaft, not shown) which in turn transmits the power to the axle(s) of the work vehicle 10 for propulsion thereof(s). to provide and / or to drive a PTO, for example, to drive an implement that is located on the work vehicle 10 or associated therewith.

An operator controls the functions of work vehicle 10, including engine system 18, powertrain 20, and work implement(s) located on or associated with work vehicle 10, from an operator station 22 in the work vehicle. Although this in 1 Although not shown, it will be appreciated that the operator station 22 includes a man-machine interface and various actuators configured to accept input commands from the operator for control of, for example, various electrical or hydraulic systems associated with controlling the aforementioned components receive, can include. The human-machine interface can be variously configured and can include one or more joysticks, various switches or levers, one or more buttons, a touchscreen interface that can be overlaid on a display, a keyboard, a speaker, a microphone, a voice recognition system associated, or various other man-machine interface devices.

Referring now to FIG 2 Various components of an example engine system 18 that may be included in the work vehicle 10 are presented according to an example implementation. The engine system 18 includes an internal combustion engine 24 (hereinafter “engine”) in the form of a diesel powered engine, but it is understood that the engine 24 could also run on other liquid fuels, such as petroleum. As gasoline or ethanol, could be operated. The engine 24 of the engine system 18 includes an engine block 26 having a piston and cylinder assembly 28 therein operable to generate combustion events. In the illustrated implementation, the engine 24 is an inline six cylinder (R-6) engine; however, different motor types and configurations may be used in alternative implementations.

The engine system 18 further includes an intake manifold 30 fluidly connected to the engine 24, an exhaust manifold 32 fluidly connected to the engine 24, and a turbocharger assembly 34. In the illustrated embodiment, the turbocharger assembly 34 includes a pair of series-connected turbochargers 36 , 38 that are fluidly connected and operatively connected to intake manifold 30 and exhaust manifold 32, although it is understood that in other embodiments engine system 18 could instead include only a single turbocharger. The turbocharger assembly 34, as shown in FIG 2 a low pressure (LP) turbocharger 36 and a high pressure (HP) turbocharger 38 arranged in series - each of the turbochargers 36, 38 having a turbine 40, 42 and a compressor 44, 46 mechanically connected via a rotary shaft 48 are included. During operation of each of the turbochargers 36, 38, exhaust gas flowing through the turbine 40, 42 causes the turbine to rotate, which in turn causes the shaft 48 to rotate. The rotation of the shaft 48, in turn, causes the compressor 44, 46 to also rotate, thereby drawing additional air into the compressors 44, 46, thereby increasing the flow rate of air to the intake manifold 30 above what it would otherwise be without the turbochargers 36, 38 would lie, and in this way the turbochargers 36, 38 supply the engine 24 with so-called "charged air".

As indicated, the HP and LP turbochargers 38, 36 are arranged in series with respect to one another. The HP turbocharger 38 includes a turbine 42 (HP turbine) for receiving exhaust gas from the exhaust manifold 32 and a compressor 46 (HP compressor) coupled with the HP turbine 42 for supplying pressurized air to the intake manifold 30 for combustion is on. The LP turbocharger 36 includes a turbine 40 (LP turbine) for receiving exhaust gas from the HP turbine 42 and a compressor 44 (LP compressor) connected to the LP turbine 40 for Supplying pressurized air to the HP compressor 46 for further pressurization is coupled on. Both the LP and HP turbochargers 36, 38 function to recover some of the thermal energy from the exhaust gas with their respective turbines 40, 42 to drive their respective compressors 44, 46, thereby increasing the amount of charge air supplied to the engine 24 is fed to incineration to increase.

According to the illustration in 2 For example, the intake manifold 30 is in flow communication with the piston and cylinder assembly 28 for directing an amount of air supply thereto. Fresh air is supplied to the intake manifold 30 from the surrounding environment via a fresh air intake duct 50 . Fresh air is drawn into the fresh air intake duct 50 , passed through an air cleaner 52 arranged in series with the fresh air intake duct 50 and supplied to the LP compressor 44 . The LP compressor 44 performs a first compression of the fresh air and feeds it to the HP compressor 46 via a charge air duct 54 . The charge air duct 54 then extends from the HP compressor 46 to the intake manifold 30 to deliver the compressed charge air from the HP compressor 46, with a charge air cooler 56 (ie, an aftercooler) positioned in series with the charge air duct 54 that regulates the temperature of the Charge air is reduced before it is supplied to the engine 24 to increase the unit mass per unit volume (ie, density) of the charge air for improved volumetric efficiency and higher power output. In one embodiment, a throttle 57 is also positioned within the charge air passage 54 to regulate the amount of compressed charge air provided to the intake manifold 30 .

The exhaust manifold 32 of the engine system 18 is flow coupled to inlets of the turbines 40, 42 of the turbochargers 36, 38 via an exhaust passage 58, with the fluid outlets of the turbines 40, 42 then being flow coupled to the surrounding environment via a breather passage 60. Exhaust gas generated by the engine 24 is directed out the exhaust manifold 32 and flows through the exhaust passage 58 to the turbines 40, 42, which exhaust gas then exits the turbines 40, 42 via the breather passage 60 to the surrounding environment in a conventional manner. An aftertreatment system 62 is placed in series with the vent passage 60 for treating the exhaust gas prior to venting the exhaust gas to the surrounding environment. The aftertreatment system 62 may include one or more components or devices that treat the exhaust, such as. a diesel particulate filter (DPF) device 64 or a selective catalytic reduction (SCR) device 65, as in FIG 2 is pictured. As will be explained in more detail below, the SCR device 65 has a high SCR conversion efficiency (for reducing NOx) when its exhaust gas is supplied at a sufficiently high temperature, and thus it is desirable to lower the temperature of the exhaust gas that undergoes the SCR Device 65 is supplied to maintain above a certain temperature threshold.

Components for modifying the flow of exhaust gas through the turbocharger assembly 34--particularly to the HP turbine 42 or both the HP and LP turbines 40, 42--are also provided in the engine system 18, it being understood that modifying the flow of exhaust gas by the turbocharger assembly 34 relates to modifying the exhaust flow provided to the turbine(s) and/or modifying the flow area of the turbine(s), both of which embodiments affect the amount of energy extracted from the exhaust. In the embodiment of 2 For example, these components are in the form of an electronic wastegate 66 (ie, "e-wastegate") and associated controller 68 that are selectively operable to modify the flow of exhaust gas supplied to the HP turbine 42 . It is also understood that a similar e-wastegate 66 could be provided for the LP turbine 40 (as in 2 shown in phantom), and thus the following discussion regarding operation/controls of the e-wastegate 66 directed to modifying the exhaust gas flow provided to the HP turbine 42 should be understood to include modifying the flow of the LP exhaust gas flow supplied to turbine 40 in one embodiment.

The e-wastegate 66 may be provided as an electronically controlled valve operable between open and closed states to selectively allow exhaust gas to bypass the HP turbine 42 and be directed into the downstream exhaust gas. The e-wastegate 66 can be either internal or external to the HP turbocharger 38 according to various implementations. The controller 68 is operable to control the electrical power supplied to the e-wastegate 66 to thereby cause the e-wastegate 66 to operate in its open or closed state, or in a position intermediate the open and closed states (e.g., closed). B. 10% open) is operated. By selectively flowing exhaust through the HP turbine 42 or bypassing the exhaust around the HP turbine 42, the e-wastegate 66 can limit the amount of power the HP turbine can use to drive the HP compressor 46 by extracting energy from it in the exhaust gas as it flows through the HP turbine 42. Likewise, as noted above, the e-wastegate 66 may also be provided to selectively exhaust exhaust to flow through the LP turbine 40 or to have the exhaust gas bypass the LP turbine 40 to reduce the amount of power the LP turbine can use to drive the LP compressor 44 by extracting energy from the exhaust gas as it passes through the LP turbine 40 flows, can generate to control.

An exhaust gas recirculation (EGR) system 70 is also included in the engine system 18 and functions to recirculate a portion of the exhaust gas produced by the engine 24, thereby reducing the formation of NOx during combustion. Exhaust is drawn from the exhaust manifold 32 and recirculated into the intake manifold 30 via the EGR system 70 . The EGR system 70 includes an EGR passage 72, an EGR cooler 74, an EGR pump 76, and an EGR mixer 78. The EGR passage 72 draws a portion of the exhaust gas flowing in the exhaust passage 58 for circulation through the EGR system 70. The EGR cooler 74 is arranged in series with the EGR passage 72 for the purpose of cooling the exhaust gas flowing through the EGR passage 72 . Exhaust flows to the EGR pump 76 , the EGR pump 76 having an inlet side 79 in flow communication with the exhaust manifold 32 and an outlet side 80 in flow communication with the intake manifold 30 . The EGR pump 76 may be a positive displacement compressor capable of providing physically metered air flow rates, such as. a Roots, screw, scroll or vane compressor, or alternatively may be a centrifugal compressor similar to a turbocharger compressor. In one embodiment, EGR pump 76 is constructed to include rotors 82 driven by electric motor 84 . The EGR pump 76 may be electrically controlled to selectively control the flow of exhaust gas recirculated from the exhaust passage 58 to the engine 24 via the EGR passage 72, including blocking the flow of exhaust gas therethrough and selectively restricting or controlling the flow of exhaust gas therethrough a desired extent. Exhaust gas pumped by the EGR pump 76 is supplied to the EGR mixer 78, which mixes the exhaust gas with the charge air supplied from the charge air duct 54 for introduction into the intake manifold 30, from which the mixture of exhaust gas and charge air is then fed into the Motor 24 is fed. In other implementations, a dedicated EGR mixer 78 may not be included in the engine system 18, with exhaust gas instead being introduced into intake ducts of the engine 24 and/or the intake manifold 30 for mixing with the charge air.

According to the illustration in 2 The engine system 18 further includes an air amplifier 85 operative to increase the amount of intake or charge air supplied to the engine 24 . In the illustrated example, the air amplifier 85 is an electric compressor 86 (hereinafter “E-Compressor”) that includes a compressor 87 driven by an electric machine 88 (ie, the electric motor). The e-compressor 86 is provided as a stand alone component that is separate from the turbocharger assembly 34 and may be positioned in any of a number of locations relative to the turbocharger assembly 34 . In the illustrated example, the E-compressor 86 is positioned downstream of the charge air cooler 56, however, it should be understood that the E-compressor 86 is instead upstream of the compressors 44, 46 of the turbocharger assembly 34, between the compressors 44, 46, between the HP compressor 46 and the charge air cooler 56 or downstream of the EGR mixer 78 could be positioned. When activated, the electric machine 88 receives input power and in response drives the compressor 87 to provide an increased flow of charge air to the engine 24 . During periods when the e-compressor 86 is not operating, intake air may bypass the e-compressor 86 via a bypass valve 89 of the air amplifier 85 arranged in parallel with the e-compressor 86 . The bypass valve 89 may be a mechanically or electrically actuated valve that operates in conjunction with the e-compressor 86 to control intake airflow therethrough.

An electrical system 90 is provided in engine system 18 for supplying electrical power to e-wastegate 66, EGR pump 76, and e-compressor 86 and includes one or more energy storage devices, inverters, converters, wiring, and other electrical components can. In one example, the electrical system 90 includes an energy storage device 92 in the form of a lithium-ion battery, although other high voltage or high power energy storage devices may be substituted, such as a lithium ion battery. B. other battery types, a supercapacitor or a combination of supercapacitors and / or batteries. The energy storage device 92 supplies DC power to a DC-DC converter (not shown) that outputs power to a DC bus 94, the DC bus 94 being a plurality of devices, outlets, etc. in the engine system 18 including the e-wastegate 66, the EGR pump 76 and the E-compressor 86 supplies power. In one implementation, the electrical system 90 is configured to provide a voltage of 36V or more, e.g. B. a 48V system, which in combination with the engine 24 a "mild hybrid" engine system for the work vehicle 10 ( 1 ) forms.

According to the illustration in 2 The engine system 18 includes a control system 102 that includes a controller 104 or electronic control unit (ECU) includes. The controller 104 includes a processor 104a and a memory 104b. Processor 104a performs the computation and control functions of controller 104 and may be any type of processor or multiple processors, single integrated circuits such as. a microprocessor or any suitable number of integrated circuit devices and/or circuit boards cooperating to accomplish the functions of a processing unit. During operation, the processor 104a executes one or more programs, which may be contained in the memory 104b, and thus controls the general operation of the controller 104 and the computer system of the controller 104 in performing the functions described herein. In the illustrated embodiment, the memory 104b stores the program(s) mentioned above.

In general, the controller 104 is used to provide at least some of the engine system operations and functions described herein, and specifically controls the operation of the e-wastegate 66, the air intensifier 85, and the EGR pump 76. In general, the controller 104 is operable to do the following coupled to: the motor 24; the EGR pump 76; the E compressor 86; the e-wastegate 66; an engine speed sensor 106; a sensor(s) 108, which may include mass air flow, temperature, and/or pressure sensors, in the intake manifold 30, charge air duct 54, or EGR duct 72; a fuel sensor 110 and an exhaust gas temperature sensor 111. Although the sensors 106, 108, 110, 111 in 2 are shown as separate dedicated sensors, it is understood that sensing capabilities for measuring some parameters may be integrated into engine system 18 components. The controller 104 may also be coupled to other devices necessary to provide the desired system control functions, including various other actuators and sensors. The controller 104 receives inputs from the various sensors that generate signals proportional to various physical parameters associated with various components in the engine system 18 and any other sources. In some embodiments, the controller 104 may be configured to provide other functions of the work vehicle 10 in addition to the control functions disclosed herein.

Controller 104 operates controlling engine system 18 (and engine 24) in various control modes, where controller 104 operates the engine in various modes based on inputs it receives, which may include sensor inputs and/or operator command inputs. The various modes of operation may include, for example, an engine start mode, an engine stop/start mode, a cold engine mode, a boost mode, and a low load engine emissions control mode (hereinafter "emissions control mode", it being understood that emissions affect at least one controlled in some manner during any/all engine operating modes), and the controller 104 may output control signals to one or more components in the engine system 18 to control operation of the engine system 18 in a specific mode.

According to one embodiment, when operating engine system 18 to control emissions, particularly when engine 24 is operating at a light load, controller 104 is configured to selectively operate e-wastegate 66 to reduce NOx emissions from engine system 18 be limited. The controller 104 may cause the engine system 18 to operate in the emissions control mode of operation when the controller 104 determines or identifies that NOx emissions may reach prohibited levels (i.e., above acceptable emissions levels), the controller 104 receiving engine load inputs (e.g., determined by airflow and fuel as requested/required) and engine load rate of change, exhaust gas temperature and engine speed to determine whether NOx emissions may be at prohibited levels at the current operating condition of the engine system 18 . That is, it is recognized that operating the engine 24 at a low engine load may result in increases in NOx emission levels from the engine system 18, which may be due to an increase in the air/fuel ratio in the engine 24 due to low load operation (resulting in lower exhaust gas temperatures and reduced conversion efficiency in the aftertreatment system 62, i.e., the SCR device 65). Accordingly, upon entering the emissions control mode, the controller 104 controls operation of the e-wastegate 66 to reduce NOx emissions from the engine system 18 .

When it is determined by the controller 104 that the engine load and exhaust gas temperature values have fallen below the respective predetermined engine load and exhaust gas temperature thresholds, respectively (or that a (falling) engine load rate of change is such that an engine load below the engine load threshold is imminent), the controller causes 104 that the engine system 18 is operating in emission control mode, since such values indicate that NOx emission levels are at prohibited levels. In emissions control mode of operation at a low load, the controller 104 causes the regulator 68 and the e-wastegate 66 (such as e.g., via the DC bus 94), the regulator 68 controls the voltage/current supplied to the e-wastegate 66 to cause the e-wastegate 66 to open (into a fully open or substantially open position). Upon opening the e-wastegate 66, the exhaust gas flow to the HP turbine 42 is modified--the exhaust flowing through the e-wastegate 66 and bypassing the HP turbine 42 when the e-wastegate 66 is in its open (or substantially open ) state is operated. By bypassing the HP turbine 42, the amount of energy extracted from the exhaust gas by the HP turbine 42 is reduced or possibly eliminated. This allows the exhaust gas to hold more thermal energy, so that the exhaust gas then flows to the aftertreatment system 62 (ie, to the SCR device 65) at a higher temperature, thereby allowing the SCR device 65 to perform NOx treatment with a performs higher conversion efficiency. Additionally, by reducing or eliminating the extraction of energy from the exhaust by the HP turbine 42 , the power to drive the HP compressor 46 is reduced such that the HP compressor 46 outputs less charge air to the intake manifold 30 . This results in a lower air-to-fuel ratio in the engine 24, which also serves to reduce NOx emissions levels produced by the engine system 18.

In combination with the control of the e-wastegate 66 during the emissions control mode of operation, the controller 104 also controls the operation of the EGR pump 76 with continued operation of the engine system 18, both when operating in the emissions control mode and when operating in other modes. The EGR pump 76 operates to recirculate exhaust gas discharged from the exhaust manifold 32 to the intake manifold 30 after mixing with charge air, thereby reducing NOx emission levels from the engine 24 . Most advantageously, the EGR pump 76 can be operated to recirculate exhaust even at low engine speeds (compared to systems that include an EGR valve rather than a pump), so that the operating range of the engine system 18 over which NOx emissions can be managed is expanded.

The air amplifier 85 is also selectively operated by the controller 104 and may also be linked to the operation of the e-wastegate 66 in one implementation. That is, the controller 104 may determine that a rate of engine load change is increasing to such an extent that activation of the air amplifier 85 is required to improve transient engine 24 response. When the engine 24 is rapidly transitioning from a low load condition to a high load condition during transient operation, activation of the air amplifier 85 allows the engine system 18 to maintain responsiveness by increasing the flow of charge air supplied to the engine 24 . Under such conditions, the engine system 18 exits the emissions control mode, with the controller 104 (and regulator 68) causing the e-wastegate 66 to be actuated to the closed (or a substantially closed) position. At the same time, the controller 104 causes power to be supplied to the e-compressor 86 from the energy storage device 92 so that the electric machine 88 receives power (e.g., from the DC bus 94) and drives the compressor 87 accordingly, thereby inducing the intake charge air into the engine 24 is boosted and a corresponding boost in torque output by the engine 24 (when accompanied by increased fuel flow supplied to the engine 24) is provided. In addition, the bypass valve 89 is caused to close to direct air through the E-compressor 86 .

Accordingly, based on monitoring engine system 18 operating parameters, including engine load, engine load rate of change, exhaust gas temperature, and engine speed, controller 104 is able to determine an appropriate operating mode for engine system 18 and transition between operating modes as needed. Based on those monitored operating parameters, the controller 104 may cause the engine system 18 to transition into the emissions control mode where the e-wastegate 66 is selectively operated to limit NOx emissions from the engine system 18--i.e. that is, the e-wastegate 66 is opened (to a fully open or substantially open position). Further, based on those monitored operating parameters, controller 104 may cause engine system 18 to exit emissions control mode, closing (or substantially closing) e-wastegate 66 and activating e-compressor 86 to boost charge air into the intake manifold 30 to improve the engine's response to the increasing load - i. That is, the closing of the e-wastegate 66 is synchronized with the activation/starting of the e-compressor 86 to provide a dual benefit to the engine 24 transient response. In addition, the EGR pump 76 allows for further NOx emission reductions over a wide operating range of the engine system 18 because the EGR pump 76 provides EGR even when the engine 24 is running at a low speed.

Referring now to FIG 3 Illustrated is an engine system 112 according to another embodiment. The engine system 112 has with the engine system 18 of 2 many components in common, and thus the components common to the components of the system are consistently considered to be those in 2 identified. However, in the engine system 112, alternative components are provided for modifying the exhaust gas flow through the turbocharger assembly 34 (instead of the e-wastegate 66 and regulator 68) and an alternative air amplifier 114 (in lieu of the e-compressor 86).

In the illustrated embodiment, the components for modifying the flow of exhaust gas through the turbocharger assembly 34 are in the form of a variable geometry (VG) turbocharger 116 (ie, a "VG turbocharger") and an associated controller 118 selectively operable to affect the flow of exhaust gas to be modified by the VG turbocharger 116. The VG turbocharger 116 can replace the HP turbocharger 38 included in the turbocharger assembly 34 ( 2 ) is included, or in other words, the HP turbocharger 38 included in the turbocharger assembly 34 may be modified/designed to be in the form of a VG turbocharger 116 rather than a standard non-variable geometry turbocharger. The VG turbocharger 116 is configured so that the aspect ratio of the turbine 120 (an HP turbine) therein can be changed, thereby changing the flow area thereof (ie modifying the exhaust flow therethrough) by the amount of from the turbine energy extracted from the exhaust gas, thereby also varying the extent to which the associated compressor 122 (an HP compressor) is driven. According to embodiments, the aspect ratio of the turbine 120 may be modified by a number of suitable means including (for example) changing the effective width of the blades in the turbine, such as by moving the turbine 120 along its axis to partially enclose the blades in the turbine housing to move in. The controller 118 may be configured to adjust the aspect ratio of the turbine 120 by moving or actuating components therein, such as. e.g., moving the turbine 120 along its axis to modify blade width, and thus the controller 118 may be provided in one example as a servomotor or other actuator selectively operable to provide such movement/actuation .

Furthermore, the air booster 114 provided in the engine system 112 is in the form of an electric turbocharger 124 (hereinafter “electric turbocharger”) that acts to increase the amount of intake or charge air supplied to the engine 24 . In the illustrated embodiment, the VG turbocharger 116 is further modified to be in the form of an EV turbocharger 124, thereby providing a VG EV turbocharger 128, although it is understood that an EV turbocharger 124 is present in the engine system 112 could be provided, which is not a VG turbocharger. Additionally, in the example depicted, the e-turbocharger 124 acts as an HP turbocharger in a turbocharger assembly 125 of the engine system 112, although it is understood that during operation of the engine system 112, the e-turbocharger 124 may occur to operate , while the LP turbocharger 36 is not operating.

In contrast to the HP turbocharger 38 in 2 The e-turbocharger 124 further includes an electric machine 126 (ie, an electric motor) mechanically coupled to the shaft 48 to selectively cause its rotation, e.g. B. during periods when there is insufficient exhaust gas to drive the turbine 120 and thereby the shaft 48 and the compressor 122, and/or when additional power is desired to drive the shaft 48. The e-turbocharger 124 may receive electrical power from the electrical system 90 of the engine system 112 , with power being supplied to the e-turbocharger 124 via the DC bus 94 from the energy storage device 92 . When activated, the electric machine 126 receives input power and in response drives the shaft 48 and thereby the compressor 122 to provide an increased flow of charge air to the engine 24 .

As previously with reference to the embodiment of FIG 2 described, the controller 104 is configured to control operation of the engine system 112 in various modes of operation, including an emissions control mode of operation when the controller 104 determines or identifies that NOx emissions may reach prohibited levels (ie, exceed acceptable emissions levels), where the controller 104 receives inputs on engine load (e.g., determined by airflow and fuel as requested/required) and engine load rate of change, exhaust gas temperature, and engine speed to determine whether NOx emissions may be at prohibited levels at the current operating condition of the engine system 112.

If it is determined by the controller 104 that the engine load and exhaust gas temperature values have fallen below the respective predetermined engine load and exhaust gas temperature thresholds, respectively (or that a (falling) engine load rate of change is such that an engine load is below the engine load threshold rating is imminent), the controller 104 causes the engine system 112 to operate in the emissions control mode of operation to manage NOx emissions. In the emissions control mode of operation at a low load, the controller 104 causes the controller 118 to be supplied power from the energy storage device 92 (such as via the DC bus 94), where the controller 118 then adjusts the aspect ratio of the turbine in the VG turbocharger 116 (ie, turbine 120) is modified to reduce the amount of energy extracted by turbine 120 from the exhaust gas. This allows the exhaust gas to hold more thermal energy, so that the exhaust gas then flows to the aftertreatment system 62 (ie, to the SCR device 65) at a higher temperature, thereby allowing the SCR device 65 to perform NOx treatment with a performs higher conversion efficiency. Additionally, by reducing the extraction of energy from the exhaust gas by the turbine 120 , the power to drive the compressor 122 is reduced such that the compressor 122 outputs less charge air to the intake manifold 30 . This results in a lower air-to-fuel ratio in the engine 24, which also serves to reduce NOx emissions levels produced by the engine system 112.

Furthermore, the controller 104 may selectively control the power provided to the EGR pump 76 (such as via the DC bus 94 ) from the energy storage device 92 to provide EGR in the engine system 112 . When the EGR pump 76 is activated (eg, the electric motor 84 rotates the rotors 82), the EGR pump 76 directs exhaust gas out of the exhaust manifold after mixing with charge air, which may be performed in the EGR mixer 78, for example 32 back to the intake manifold 30. This mixing of recirculated exhaust gas with the charge air also serves to reduce NOx emission levels produced by the engine system 112, both during low speed operation of the engine 24 and at higher operating speeds.

The air amplifier 114 is also selectively operated by the controller 104 and may also be associated with changing the aspect ratio of the turbine in the VG turbocharger 116 in one implementation. That is, the controller 104 may determine that a rate of engine load change is increasing to such an extent that activation of the air amplifier 114 is required. When the engine 24 transitions rapidly from a low load condition to a high load condition during transient operation, the controller 104 causes the engine system 112 to exit the emissions control mode, with the controller 104 (and the controller 118) controlling such a change in the aspect ratio of the turbine 120 in the VG turbochargers 116 cause more energy to be extracted from the exhaust. At the same time, the controller 104 causes power to be supplied to the e-turbocharger 124 from the energy storage device 92 such that the electric machine 126 receives power (eg, from the DC bus 94) and drives the shaft 48 and compressor 122 accordingly, thereby causing the The amount of charge air supplied to the engine 24 is boosted and a corresponding boost in torque output from the engine 24 (when accompanied by increased fuel flow supplied to the engine 24) is provided to accommodate the increased load will.

Although the in 2 and 3 While the engine systems 18, 112 shown include a specified combination of components for modifying exhaust gas flow through the turbocharger assembly 34, 125 and air amplification components, it should be understood that the engine systems could be provided with various combinations of components. For example, an engine system could be provided that includes an e-wastegate 66 for modifying exhaust flow through the turbocharger assembly 34 in combination with an e-turbocharger 124 for boosting charge air into the intake manifold 30 ( 4 ), or an engine system could be provided that includes a VG turbocharger 116 to modify the exhaust gas flow through the turbocharger assembly 125 in combination with an E-compressor 86 to boost the charge air into the intake manifold 30 ( 5 ). In yet another implementation, an engine system could be provided that includes an e-wastegate 66, an e-compressor 86, and a VG e-turbocharger 128 ( 6 ).

Referring now to FIG 7 and with further reference to 1-6 1, a flowchart is provided for a method 130 for operating the engine system 18, 112, which may be performed by the controller 104, for example, according to the present disclosure. In general, the method 130 is implemented during operation of the work vehicle 10 . As discussed in more detail below, the method 130 implements a control strategy for selectively operating electrified air system components in the engine system 18, 112 to manage NOx pollutant emissions.

The method 130 begins at step 132 with a determination of engine system operating conditions. The determination of engine system operating conditions may be made based on ongoing monitoring and analysis of various operating parameters of the engine system 18, 112, which may include, for example, the following nen: engine speed; engine load; engine load change rate; Air mass flow, temperature and pressure for intake/charge air or exhaust gas; fuel flow; Exhaust gas temperature and/or estimated NOx concentration. Based on the determined engine operating mode and as part of step 132, the controller 104 may operate to issue command and control signals that are sent to and received by the components of the engine system 18, 112 and direct the operation of the engine system in an appropriate operating mode (e.g., . B. engine start mode, engine stop/start mode, cold engine mode, boost mode, or engine emissions control mode), such command and control signals being provided as non-limiting examples to the engine 24, the EGR pump 76, the E -Compressor 86 or the e-turbocharger 124 and the air amplifier 85, 114 are transferred.

During continued operation of the engine system 18, 112 in a particular mode, the method 130 proceeds to step 134 where a calculation of desired exhaust gas recirculation (EGR) values and air/fuel ratio appropriate for the particular operating mode is performed becomes. Again, the engine system operating mode may be based on ongoing monitoring and analysis of, for example, engine speed; engine load and air mass flow, temperature and pressure for intake/charged air or exhaust gas; fuel flow and/or exhaust gas temperature along with demands on the engine system 18, 112 in response to operator commands. Based on the current mode of operation, appropriate EGR levels and air/fuel ratio are calculated for operation in that mode.

The method 130 also monitors the state of charge of the energy storage device 92 as indicated at step 136 while continuously monitoring and analyzing the operating parameters of the engine system 18, 112 and along with calculating the EGR and air/fuel ratio setpoints. Based on this monitoring of the state of charge of the energy storage device, a determination is made at step 138 as to whether the electrical system 90 in the engine system 18, 112 is activated. If it is determined at step 138 that the electrical system 90 is not activated, such as B. based on the energy storage device 92 not having sufficient charge level as indicated at 140, the method 130 proceeds to step 142 where the control scheme is exited and the method 130 begins again. Alternatively, if it is determined at step 138 that the electrical system 90 is activated, such as B. based on the energy storage device 92 having a sufficient state of charge, as indicated at 144, the method 130 continues by working along a number of parallel operational paths.

Along two operational paths of continued method 130, comparisons are made between air/fuel ratio and associated positive and negative air/fuel ratio threshold values, as indicated at steps 146 and 147. More specifically, a difference between an actual air/fuel ratio and the desired air/fuel ratio (i.e., an "AVV error") is compared to the positive and negative AVG error thresholds at steps 146 and 147 - where Step 146 determines whether the ATR error is greater than the positive ATR error threshold, and step 147 determines whether the ATR error is less than the negative ATR error threshold. In performing steps 146 and 147, the controller 104 first calculates the AFR error by comparing an actual air/fuel ratio to the desired air/fuel ratio. The actual air/fuel ratio may be determined by controller 104 based on inputs received from fuel sensor 110 and sensor(s) 108 (measuring, for example, mass air flow and/or pressure in intake manifold 30 or charge air duct 54). will. Upon calculating the ATR error, the controller 104 may then compare the ATR error to predetermined positive and negative ATR error thresholds, which may be stored in memory 104b, for example, to determine whether the ATR error is within a acceptable margin of deviation within which the electrified air system components in the engine system 18, 112 can operate.

With respect to step 147, if at step 147 it is determined that the ATR Deviation is less than the negative ATR Deviation threshold, as indicated at 148, the method 130 proceeds to step 149 where power to activate the system is applied to the air amplifier 85, 114 (ie, the e-compressor 86 or the e-turbocharger 124, as will be described in more detail below). That is, if the ATR deviation is less than the negative ATR deviation threshold, it is determined that the ATR deviation is not within an acceptable deviation range and that the need to manage NOx emissions by modifying the exhaust flow is increasing the/through the turbocharger assembly 34, 125 (which may result in a reduction in the amount of charge air supplied to the engine 24) is thus small. This may occur when the engine 24 is operating above a predetermined minimum engine load threshold and/or when the engine load is increasing increases at a higher rate (above an associated rate-of-change threshold). In such cases, the controller 104 operates to cause power to be applied to the air booster 85, 114 so that boosted charge air is delivered to the intake manifold 30. Alternatively, if it is instead determined at step 147 that the ACR Deviation is not less than (ie, greater than) the negative ACR Deviation threshold, as indicated at 150, the method 130 proceeds to step 151, where from the control scheme is exited and the method 130 begins again.

With respect to step 146 , if it is determined at step 146 that the ACR error is greater than the positive ACR error threshold, the method 130 proceeds such that it is not within an acceptable error band, as indicated at 152 , proceeds to steps 154 and 156 where next determinations are made as to whether the exhaust gas temperature is below a predetermined exhaust gas temperature threshold (step 154) and whether the engine load is below a predetermined engine load threshold (step 156). In determining whether exhaust gas temperature and engine load are below predetermined exhaust gas temperature threshold and engine load threshold, respectively, controller 104 may receive inputs from exhaust gas temperature sensor 111 and sensor(s) 108, 110 (controller 104 may determine engine load based on from the sensors 108, 110 determine/calculate measured air flow and fuel flow), the measured exhaust gas temperature and the determined engine load being compared with the respective threshold values which may be stored in memory 104b, for example. Alternatively, if it is determined at step 146 that the ATR error is not greater than (i.e., less than) the positive ATR error threshold, as indicated at 157, the method 130 proceeds to step 159 where from the control scheme is exited and the method 130 begins again.

If it is determined at steps 154 and 156 that the exhaust gas temperature is above the exhaust gas temperature threshold (step 154) or that the engine load is above the engine load threshold (step 156), as indicated at 158, then the method 130 proceeds to step 160 or step 162 above, where the control scheme is exited and the method 130 begins again. Alternatively, if it is determined at steps 154 and 156 that the exhaust gas temperature is below the exhaust gas temperature threshold (step 154) and that the engine load is also below the engine load threshold (step 156), as indicated at 164, then the method 130 proceeds to step 166 above, where the controller 104 operates to cause the exhaust gas flow through the turbocharger assembly 34, 125 (i.e., the HP turbine 42, 120) to be modified such that less energy is extracted from the exhaust gas.

In one embodiment, at step 166, the controller 104 causes power to be applied to the e-wastegate 66 (as controlled by the controller 68) such that the e-wastegate 66 moves to an open position (a fully open or an intermediate position). Substantially open position) is actuated. Upon opening the e-wastegate 66, exhaust flow to the HP turbine 42 is modified -- with the exhaust flowing through the e-wastegate 66 and bypassing the HP turbine 42 when the e-wastegate 66 is in an open (or substantially open ) state is operated. Bypassing the HP turbine 42 reduces (or eliminates) the amount of energy extracted from the exhaust gas by the HP turbine, thereby allowing the exhaust gas to hold more thermal energy (allowing the SCR device 65 performs the NOx treatment with a higher conversion efficiency), thereby reducing the power driving the HP compressor 46 (so that the compressor 46 outputs less charge air to the intake manifold 30, resulting in a lower air/fuel ratio in leads to the engine).

In another embodiment, at step 166, the controller 104 causes power to be applied to the governor 118 to vary the aspect ratio of the HP turbine 120 in a VG turbocharger 116, where the governor 118 varies the aspect ratio of the HP turbine 120 Moving or operating components therein, such as e.g. B. moving the HP turbine 120 along its axis to modify blade width. Varying the HP turbine 120 aspect ratio reduces the amount of energy extracted from the exhaust gas by the turbine, allowing the exhaust gas to hold more heat energy (allowing the SCR device to perform NOx treatment with a performs higher conversion efficiency), and thereby reducing the power driving the compressor 122 (so that the compressor 122 outputs less charge air to the intake manifold 30, resulting in a lower air/fuel ratio in the engine 24).

By modifying (reducing) the flow of exhaust gas through the turbocharger assembly 34, 125 (ie, the HP turbine 42, 120) at step 166, the air/fuel ratio in the engine 24 can be reduced. The controller 104 may control the e-wastegate 66 or the VG turbocharger 116 to continue modifying the exhaust gas flow through the turbocharger assembly 34, 125 until it is determined (by continued sensor inputs to the controller 104) that the air/fuel ratio is low met a target value. With the air/fuel ratio at a target value, the amount of excess air present during combustion is reduced, thereby reducing levels of NOx emissions emitted from the engine 24 .

After effecting the modification of exhaust gas flow through the turbocharger assembly 34, 125 at step 166, the method 130 may continue to monitor a rate of change of engine load. In monitoring the engine load rate of change, a determination is made at step 168 as to whether the engine load rate of change exceeds an engine load rate of change threshold value, since it is understood that a large increase in engine load rate of change would require rapid transient response of the engine 24 (via boosting the intake air supplied to the engine 24). to cope with the increased load. If it is determined at step 168 that the engine load rate of change exceeds the engine load rate of change threshold, as indicated at 170, the method proceeds to step 172 where the electrified air booster 85, 114 (i.e., the e-compressor 86 or the e-turbocharger 124, as (described in more detail below) is activated so that boosted charge air is supplied to the intake manifold 30 . Further, at step 172, when the electrified air amplifier 85, 114 is activated, the controller 104 operates to cease modifying the exhaust gas flow through the turbocharger assembly 34, 125 (i.e., the HP turbine 42, 120), such as, for example, by activating the e-wastegate 66 or the VG turbocharger 116. If instead it is determined at step 168 that the engine load rate of change does not exceed the engine load rate of change threshold, as indicated at 174, the method 130 continues - with the controller 104 determining to that effect operation to modify the exhaust gas flow through the turbocharger assembly 34, 125 (i.e., the HP turbine 42, 120) by selectively operating the E-wastegate 66 or the VG turbocharger 116.

Referring again to the progression of the method 130 following the determination made at step 138 and now along the alternate path of operation of the continued method 130, at step 176 control of the EGR pump 76 is performed. As previously indicated, at step 134 a calculation is made as to an amount of EGR that is desired for a current mode of operation of the engine system 18, 112 -- the mode of operation being based on ongoing monitoring and analysis of various engine system operating parameters, including monitoring engine speed, is determined. At step 176, the controller 104 operates the EGR pump 76 a desired amount to meet the target amount of EGR, such as. B. Controlling the power supplied to the electric motor 84 to rotate the rotors 82 in the EGR pump 76. The EGR pump 76 is thus operated in a controlled manner to deliver exhaust gas from the exhaust manifold 32 to the intake manifold 30 after mixing with charge air this mixing of recirculated exhaust gas with the charge air serves to reduce levels of NOx emissions produced by the engine system 18,112. Advantageously, the EGR pump 76 can be operated even with the engine 24 running at low speed so that exhaust gas recirculation and associated NOx emissions management can be provided over a wide range of engine system operating conditions.

Upon completion of step 149 or 166/172, along with step 176, the method 130 may then end as indicated at step 178, it being understood that the method 130 is repeated as the engine system 18, 112 continues to operate to continuously manage the NOx emissions thereof. Advantageously, performance of the method 130 and the structure of the engine system 18, 112 operated in accordance with that method facilitates the management of NOx emissions from the engine system 18, 112 over a wide range of operating conditions, including operation at low loads and low speeds , allowed. The NTE range in which NOx emissions are managed is thus expanded compared to existing engine systems, thereby allowing the engine system 18, 112 of the disclosed invention to meet more stringent NOx emission regulations of the future. Electrified air system components in the engine system 12, 118 are selectively operable to better manage NOx emissions, operation of the air system components controlling EGR and improving SCR conversion efficiency, particularly at low speed, low load engine operating conditions such that NOx Emissions can be reduced over an extended NTE range. Depending on the driving cycle, the engine system 12, 118 can provide a tenfold reduction in NOx emissions compared to existing engine systems such as e.g. a reduction of 0.4 g/kW-h to 0.04 g/kW-h.

• 1. Ein Motorsystem umfasst einen Motor mit einer oder mehreren Kolben-Zylinder-Anordnungen, die mit einem Einlasskrümmer und einem Auslasskrümmer in Verbindung stehen, einen Turbolader, der eine Turbine, die mit dem Auslasskrümmer in Verbindung steht, und einen Verdichter, der von der Turbine angetrieben wird und mit dem Einlasskrümmer in Verbindung steht, umfasst, und einen Regler, der dazu konfiguriert ist, einen Abgasstrom durch die Turbine zu steuern. Das Motorsystem umfasst des Weiteren eine Steuerung, die eine Prozessor- und Speicherarchitektur aufweist und die mit dem Regler wirkverbunden ist, wobei die Steuerung dazu konfiguriert ist, eine Motorlast und eine Abgastemperatur während des Betriebs des Motors zu überwachen, verbotene Motorstickoxid(NOx)-Emissionswerte basierend auf der Motorlast und der Abgastemperatur, bei denen die NOx-Emissionen innerhalb eines verbotenen Bereichs liegen, zu identifizieren und, wenn die verbotenen Motorstickoxid(NOx)-Emissionswerte identifiziert wurden, den Regler dahingehend zu steuern, den Abgasstrom durch die Turbine zu modifizieren. Durch das Modifizieren des Abgasstroms durch die Turbine wird eine Menge an Energie, die von der Turbine aus dem Abgas extrahiert wird, reduziert und wird die dem Verdichter zugeführte Antriebskraft reduziert, wodurch ein dem Einlasskrümmer von dem Verdichter zugeführter Einlassluftstrom reduziert wird.
• 2. Das Motorsystem nach Beispiel 1, wobei die Steuerung dazu konfiguriert ist, ein Soll-Luft/Kraftstoff-Verhältnis für den Betrieb des Motors zu bestimmen, zu bestimmen, ob ein Ist-Luft/Kraftstoff-Verhältnis mit dem Soll-Luft/Kraftstoff-Verhältnis übereinstimmt, und, wenn das Ist-Luft/Kraftstoff-Verhältnis nicht mit dem Soll-Luft/Kraftstoff-Verhältnis übereinstimmt oder nicht innerhalb eines vorbestimmten Bereichs in Bezug auf das Soll-Luft/Kraftstoff-Verhältnis liegt, den Abgasstrom durch die Turbine zu modifizieren, so dass das Luft/Kraftstoff-Verhältnis für den Betrieb des Motors reduziert wird.
• 3. Das Motorsystem nach Beispiel 1, wobei die Steuerung dazu konfiguriert ist, die Motorlast und die Abgastemperatur mit einem zugehörigen Motorlastschwellenwert bzw. Abgastemperaturschwellenwert zu vergleichen, die verbotenen Motorstickoxid(NOx)-Emissionswerte zu identifizieren, wenn sowohl die Motorlast als auch die Abgastemperatur unter dem zugehörigen Motorlastschwellenwert bzw. Abgastemperaturschwellenwert liegen, und den Regler dahingehend zu steuern, den Abgasstrom durch die Turbine zu modifizieren, um die Menge an von der Turbine aus dem Abgas extrahierter Energie zu reduzieren und die dem Verdichter zugeführte Antriebsleistung zu reduzieren, bis die Abgastemperatur eine Zieltemperatur erreicht.
• 4. Das Motorsystem nach Beispiel 1, wobei der Turbolader einen Turbolader mit variabler Geometrie (VG) umfasst, wobei die Turbine ein einstellbares Seitenverhältnis aufweist, durch das die Menge an Energie, die aus dem Abgas extrahiert wird, wenn das Abgas dort hindurchströmt, gesteuert wird, und wobei der Regler dazu konfiguriert ist, die Positionierung einer oder mehrerer Komponenten in der Turbine zur Einstellung des Seitenverhältnisses einzustellen.
• 5. Das Motorsystem nach Anspruch 1, das ferner ein elektrifiziertes Wastegate umfasst, das zwischen einer geöffneten Stellung und einer geschlossenen Stellung betreibbar ist, um zu bewirken, dass der Abgasstrom durch die Turbine hindurchströmt oder die Turbine umgeht, und wobei der Regler dazu konfiguriert ist, das elektrifizierte Wastegate zwischen der geöffneten Stellung und der geschlossenen Stellung zu betätigen.
• 6. Das Motorsystem nach Beispiel 5, wobei der Turbolader ein Hochdruck(HP)-Turbolader ist und die Turbine und der Verdichter eine HP-Turbine und ein HP-Verdichter sind, wobei das elektrifizierte Wastegate zwischen der geöffneten Stellung und der geschlossenen Stellung dahingehend betreibbar ist, zu bewirken, dass der Abgasstrom durch die HP-Turbine hindurchströmt oder die HP-Turbine umgeht, und wobei das Motorsystem ferner einen Niederdruck(LP)-Turbolader umfasst, der eine LP-Turbine und einen LP-Verdichter und ein anderes elektrifiziertes Wastegate, das zwischen einer geöffneten Stellung und einer geschlossenen Stellung dahingehend betreibbar ist, zu bewirken, dass der Abgasstrom durch die LP-Turbine hindurchströmt oder die LP-Turbine umgeht, aufweist, und wobei der Regler dazu konfiguriert ist, das andere elektrifizierte Wastegate zwischen der geöffneten Stellung und der geschlossenen Stellung zu betätigen.
• 7. Das Motorsystem nach Beispiel 1, wobei die Steuerung dazu konfiguriert ist, beim Überwachen der Motorlast sowohl eine Motorlasthöhe als auch eine Motorlaständerungsrate zu überwachen, und wobei die Steuerung ferner dazu konfiguriert ist, eine Motordrehzahl des Motors zu überwachen.
• 8. Das Motorsystem nach Beispiel 7, das ferner einen elektrifizierten Luftverstärker umfasst, der dazu konfiguriert ist, bei Aktivierung Einlassluft zu dem Einlasskrümmer zu verstärken.
• 9. Das Motorsystem nach Beispiel 8, wobei der elektrifizierte Luftverstärker einen E-Verdichter umfasst, der einen eigenständigen Verdichter und eine elektrische Maschine, die den eigenständigen Verdichter zum Verstärken der Einlassluft in den Einlasskrümmer antreibt, umfasst.
• 10. Das Motorsystem nach Beispiel 8, wobei der elektrifizierte Luftverstärker eine elektrische Maschine umfasst, die dahingehend mit dem Turbolader mechanisch gekoppelt ist, eine Welle, die die Turbine und den Verdichter koppelt, anzutreiben, wobei der Turbolader also einen E-Turbolader umfasst, der Einlassluft in den Einlasskrümmer verstärkt.
• 11. Das Motorsystem nach Beispiel 8, wobei die Steuerung dazu konfiguriert ist, zu identifizieren, wenn die Motorlaständerungsrate den Motorlaständerungsratenschwellenwert überschreitet, den elektrifizierten Luftverstärker zu aktivieren, wenn die Motorlaständerungsrate den Motorlaständerungsratenschwellenwert überschreitet, und bei Aktivierung des elektrifizierten Luftverstärkers den Regler dahingehend zu steuern, die Modifikation des Abgasstroms durch die Turbine zu beenden.
• 12. Das Motorsystem nach Beispiel 1, das ferner eine Abgasrückführungs(AGR)-Pumpe umfasst, die dahingehend betreibbar ist, einen Teil des aus dem Auslasskrümmer ausgegebenen Abgases zu dem Einlasskrümmer zurückzuführen, wobei die AGR-Pumpe in Kombination mit der Steuerung, die den Abgasstrom durch die Turbine modifiziert, dahingehend betreibbar ist, NOx-Emissionen aus dem Motorsystem weiter zu reduzieren.
• 13. Ein Motorsystem für ein Arbeitsfahrzeug umfasst einen Motor mit einer oder mehreren Kolben-Zylinder-Anordnungen, die mit einem Einlasskrümmer und einem Auslasskrümmer in Verbindung stehen, einen Turbolader, der eine Turbine, die mit dem Auslasskrümmer in Verbindung steht, und einen Verdichter, der von der Turbine angetrieben wird und mit dem Einlasskrümmer in Verbindung steht, umfasst, und einen Regler, der dazu konfiguriert ist, einen Abgasstrom durch die Turbine zu steuern. Das Motorsystem umfasst des Weiteren eine Steuerung, die eine Prozessor- und Speicherarchitektur aufweist und die mit dem Regler wirkverbunden ist, wobei die Steuerung dazu konfiguriert ist, eine Motorlast und eine Abgastemperatur während des Betriebs des Motors zu überwachen, zu bestimmen, ob die Motorlast und die Abgastemperatur unter einem Motorlastschwellenwert bzw. einem Abgastemperaturschwellenwert liegen, wodurch verbotene Motorstickoxid(NOx)-Emissionswerte angezeigt werden, und, wenn die Motorlast und die Abgastemperatur unter dem Motorlastschwellenwert und dem Abgastemperaturschwellenwert liegen, den Regler dahingehend zu steuern, den Abgasstrom durch die Turbine zu modifizieren. Durch das Modifizieren des Abgasstroms durch die Turbine wird eine Menge an Energie, die von der Turbine aus dem Abgas extrahiert wird, reduziert und wird die dem Verdichter zugeführte Antriebskraft reduziert, wodurch ein dem Einlasskrümmer von dem Verdichter zugeführter Einlassluftstrom reduziert wird.
• 14. Das Motorsystem nach Beispiel 13, wobei der Turbolader einen Turbolader mit variabler Geometrie (VG) umfasst, wobei die Turbine ein einstellbares Seitenverhältnis aufweist, das die Menge an Energie, die aus dem Abgas extrahiert wird, wenn das Abgas dort hindurchströmt, steuert, und wobei der Regler dazu konfiguriert ist, die Positionierung einer oder mehrerer Komponenten in der Turbine zur Einstellung des Seitenverhältnisses einzustellen.
• 15. Das Motorsystem nach Beispiel 13, das ferner ein elektrifiziertes Wastegate umfasst, das zwischen einer geöffneten Stellung und einer geschlossenen Stellung dahingehend betreibbar ist, zu bewirken, dass der Abgasstrom durch die Turbine hindurchströmt oder die Turbine umgeht, und wobei der Regler dazu konfiguriert ist, das elektrifizierte Wastegate zwischen der geöffneten Stellung und der geschlossenen Stellung zu betätigen.

The following examples are provided, numbered for ease of reference.

• 1. An engine system includes an engine having one or more piston and cylinder assemblies associated with an intake manifold and an exhaust manifold, a turbocharger including a turbine in communication with the exhaust manifold and a compressor driven by the turbine and in communication with the intake manifold, and a governor configured to direct exhaust gas flow through the turbine Taxes. The engine system further includes a controller having a processor and memory architecture and operatively connected to the governor, the controller configured to monitor engine load and exhaust gas temperature during operation of the engine, prohibited engine nitrogen oxide (NOx) emission levels based on engine load and exhaust gas temperature at which NOx emissions are within a prohibited range, and when prohibited engine nitrogen oxide (NOx) emission levels have been identified, controlling the controller to modify exhaust gas flow through the turbine. By modifying the flow of exhaust gas through the turbine, an amount of energy extracted from the exhaust gas by the turbine is reduced and motive power provided to the compressor is reduced, thereby reducing intake airflow provided to the intake manifold by the compressor.
• 2. The engine system of example 1, wherein the controller is configured to determine a desired air/fuel ratio for operation of the engine, determining whether an actual air/fuel ratio matches the desired air/fuel ratio matches, and if the actual air/fuel ratio does not match the desired air/fuel ratio or is not within a predetermined range relative to the desired air/fuel ratio, exhaust gas flow through the turbine to be modified so that the air/fuel ratio for the operation of the engine is reduced.
• 3. The engine system of example 1, wherein the controller is configured to compare the engine load and the exhaust gas temperature with an associated engine load threshold and exhaust gas temperature threshold, respectively, to identify the prohibited engine nitrogen oxide (NOx) emission levels when both the engine load and the exhaust gas temperature are below the associated engine load threshold and exhaust gas temperature threshold, respectively, and to control the controller to modify the exhaust gas flow through the turbine to reduce the amount of energy extracted by the turbine from the exhaust gas and to reduce the power input to the compressor until the exhaust gas temperature Target temperature reached.
• 4. The engine system of example 1, wherein the turbocharger comprises a variable geometry (VG) turbocharger, the turbine having an adjustable aspect ratio that controls the amount of energy extracted from the exhaust gas as the exhaust gas flows therethrough and wherein the controller is configured to adjust the positioning of one or more components in the turbine for aspect ratio adjustment.
• 5. The engine system of claim 1, further comprising an electrified wastegate operable between an open position and a closed position to cause the flow of exhaust gas to flow through the turbine or bypass the turbine, and wherein the controller is configured to do so to actuate the electrified wastegate between the open position and the closed position.
• 6. The engine system of Example 5, wherein the turbocharger is a high pressure (HP) turbocharger and the turbine and compressor are an HP turbine and an HP compressor, the electrified wastegate being operable between the open position and the closed position to that end is to cause the exhaust flow to flow through the HP turbine or bypass the HP turbine, and wherein the engine system further comprises a low pressure (LP) turbocharger having an LP turbine and an LP compressor and another electrified wastegate operable between an open position and a closed position to cause the exhaust flow to flow through the LP turbine or bypass the LP turbine, and wherein the controller is configured to position the other electrified wastegate between the open position and the closed position.
• 7. The engine system of example 1, wherein the controller is configured to monitor both an engine load level and a rate of engine load change when monitoring engine load, and wherein the controller is further configured to monitor an engine speed of the engine.
• 8. The engine system of example 7, further comprising an electrified air booster configured to boost intake air to the intake manifold when activated.
• 9. The engine system of example 8, wherein the electrified air booster comprises an e-compressor having a self-contained compressor and an electric machine using the self-contained compressor for boosting the in intake air drives into the intake manifold.
• 10. The engine system of Example 8, wherein the electrified air intensifier includes an electric machine mechanically coupled to the turbocharger to drive a shaft coupling the turbine and the compressor, ie, the turbocharger including an e-turbocharger that Reinforced intake air into the intake manifold.
• 11. The engine system of example 8, wherein the controller is configured to identify when the engine load rate of change exceeds the engine load rate of change threshold, activate the electrified air amplifier when the engine load rate of change exceeds the engine load rate of change threshold, and upon activation of the electrified air amplifier, control the controller to: stop modifying the exhaust gas flow through the turbine.
• 12. The engine system of Example 1, further comprising an exhaust gas recirculation (EGR) pump operable to recirculate a portion of the exhaust gas discharged from the exhaust manifold to the intake manifold, the EGR pump in combination with the controller operating the Exhaust flow modified through the turbine, operable to further reduce NOx emissions from the engine system.
• 13. An engine system for a work vehicle includes an engine having one or more piston and cylinder assemblies communicating with an intake manifold and an exhaust manifold, a turbocharger having a turbine communicating with the exhaust manifold, and a compressor, driven by the turbine and in communication with the intake manifold, and a governor configured to control exhaust gas flow through the turbine. The engine system further includes a controller having a processor and memory architecture and operatively connected to the governor, the controller configured to monitor an engine load and an exhaust gas temperature during operation of the engine, determine whether the engine load and the exhaust gas temperature are below an engine load threshold and an exhaust gas temperature threshold, respectively, thereby indicating prohibited engine nitrogen oxide (NOx) emission levels, and when the engine load and the exhaust gas temperature are below the engine load threshold and the exhaust gas temperature threshold, control the controller to increase the exhaust gas flow through the turbine modify. By modifying the flow of exhaust gas through the turbine, an amount of energy extracted from the exhaust gas by the turbine is reduced and motive power provided to the compressor is reduced, thereby reducing intake airflow provided to the intake manifold by the compressor.
• 14. The engine system of example 13, wherein the turbocharger comprises a variable geometry (VG) turbocharger, the turbine having an adjustable aspect ratio that controls the amount of energy extracted from the exhaust gas as the exhaust gas flows therethrough. and wherein the controller is configured to adjust the positioning of one or more components in the turbine for aspect ratio adjustment.
• 15. The engine system of example 13, further comprising an electrified wastegate operable between an open position and a closed position to cause exhaust gas flow to flow through or bypass the turbine, and wherein the controller is configured to do so to actuate the electrified wastegate between the open position and the closed position.

Thus, the foregoing has provided an engine system that manages NOx emissions over a wide operating range of the engine, including low speed and low load engine operating conditions. The engine system is provided with electrified air system components that are selectively operable to enhance exhaust gas recirculation as well as improve selective catalytic reduction conversion efficiency in the engine system to provide reductions in in-cylinder and out-of-cylinder NOx emissions. According to a control-implemented method or control scheme, electrified air system components may be activated when NOx emission levels are determined to be at prohibited levels, as determined by monitoring air/fuel ratio, engine load, and exhaust gas temperature in the engine system, with exhaust gas flow through the turbocharger assembly in the engine system and is modified by a turbine in the turbocharger assembly to reduce an amount of energy extracted from the exhaust gas by the turbine and thereby reduce NOx emissions from the engine system.

As used herein, lists of items separated by conjunctions (e.g., "and") and further preceded by the phrase "one or more of" or "at least one of" where they are not otherwise restricted or modified denomination, configuration or arrangement, which may include any one of the list items or any combination thereof. For example, "at least one of A, B, and C" or "one or more of A, B, and C" give the possibilities of just A, just B, just C, or any combination of two or more of A, B, and C ( e.g. A and B; B and C; A and C; or A, B and C). Furthermore, the use of "one or more of" or "at least one of" in the claims for certain elements does not imply that other elements are in the singular form, nor does it have any other effect on the other claim elements.

As used herein, the singular forms "a" and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. Further, it is understood that any use of the terms "comprises" and/or "comprising" herein indicates the presence of specified features, integers, steps, acts, elements and/or components, but the presence or addition of one or more other features , integers, steps, operations, elements, components and/or groups thereof.

The description of the present disclosure has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will become apparent to those skilled in the art without departing from the scope and spirit of the disclosure. Embodiments explicitly set forth herein were chosen and described in order to best explain the principles of the disclosure and its practical application, and to enable others of ordinary skill in the art to understand the disclosure and recognize many alternatives, modifications, and variations from the example(s) described. Accordingly, various embodiments and implementations other than those explicitly described are within the scope of the following claims.

Claims (15)

Engine system (18, 112) comprising: an engine (24) having one or more piston and cylinder assemblies (28) communicating with an intake manifold (30) and an exhaust manifold (32); a turbocharger (36, 38, 116, 124, 128) having a turbine (40, 42, 120) connected to the exhaust manifold (32) and a compressor (44, 46, 122) connected to the turbine (40, 42, 120) driven and in communication with the intake manifold (30); a governor (68, 118) configured to control exhaust gas flow through the turbine (40, 42, 120); and a controller (104) having a processor (104a) and memory (104b) architecture and operatively connected to the controller (68, 118), the controller (104) being configured to: monitor engine load and exhaust gas temperature during operation of the engine (24); identify prohibited engine nitrogen oxide (NOx) emission levels based on engine load and exhaust gas temperature at which NOx emissions are within a prohibited range; and if the prohibited engine oxides of nitrogen (NOx) emission levels have been identified, controlling the controller (68, 118) to modify the exhaust gas flow through the turbine (40, 42, 120); wherein by modifying the flow of exhaust gas through the turbine (40, 42, 120), an amount of energy extracted from the exhaust gas by the turbine (40, 42, 120), is reduced and driving force supplied to the compressor (44, 46, 122) is reduced, thereby reducing intake air flow supplied from the compressor (44, 46, 122) to the intake manifold (30). engine system (18, 112). claim 1 wherein the controller (104) is configured to: determine a desired air/fuel ratio for operation of the engine (24); determine whether an actual air/fuel ratio matches the target air/fuel ratio; and if the actual air/fuel ratio does not match the desired air/fuel ratio or is not within a predetermined range relative to the desired air/fuel ratio, the exhaust gas flow through the turbine (40, 42, 120) so that the air/fuel ratio for operation of the engine (24) is reduced. engine system (18, 112). claim 1 wherein the controller (104) is configured to: compare the engine load and the exhaust gas temperature to an associated engine load threshold and exhaust gas temperature threshold, respectively; identify the prohibited engine nitrogen oxide (NOx) emission levels when both the engine load and the exhaust gas temperature are below the associated engine load threshold and exhaust gas temperature threshold, respectively; and to control the controller (68, 118) to modify the flow of exhaust gas through the turbine (40, 42, 120) to reduce the amount of energy extracted from the exhaust gas by the turbine (40, 42, 120) and the the compressor (44, 46, 122) to reduce supplied drive power until the exhaust gas temperature reaches a target temperature. engine system (18, 112). claim 1 wherein the turbocharger (36, 38, 116, 124, 128) comprises a variable geometry (VG) turbocharger (116), the turbine (120) having an adjustable aspect ratio by which the amount of energy extracted from the exhaust gas is extracted as the exhaust gas flows therethrough, and wherein the controller (118) is configured to adjust the positioning of one or more components in the turbine (120) to adjust the aspect ratio. engine system (18, 112). claim 1 further comprising an electrified wastegate (66) operable between an open position and a closed position to cause the flow of exhaust gas to flow through the turbine (40, 42) or bypass the turbine (40, 42), and wherein the controller (68, 118) is configured to actuate the electrified wastegate (66) between the open position and the closed position. engine system (18, 112). claim 5 wherein the turbocharger (36, 38, 116, 124, 128) comprises a high pressure (HP) turbocharger (38) and the turbine and compressor comprise an HP turbine (42) and an HP compressor (46), wherein the electrified wastegate (66) is operable between the open position and the closed position to cause the flow of exhaust gas to flow through the HP turbine (42) or to bypass the HP turbine (42); and wherein the engine system (18, 112) further comprises: a low pressure (LP) turbocharger (36) comprising an LP turbine (40) and an LP compressor (44); and another electrified wastegate (66) operable between an open position and a closed position to cause the flow of exhaust gas to flow through the LP turbine (40) or bypass the LP turbine (40), and wherein the controller (68) is configured to actuate the other electrified wastegate (66) between the open position and the closed position. engine system (18, 112). claim 1 wherein the controller (104) is configured to monitor both an engine load level and a rate of engine load change when monitoring engine load, and wherein the controller (104) is further configured to monitor an engine speed of the engine (24). engine system (18, 112). claim 7 Further comprising an electrified air booster (85, 114) configured to boost intake air to the intake manifold (30) when activated. engine system (18, 112). claim 8 , wherein the electrified air booster (85, 114) comprises an e-compressor (86) having a self-contained compressor (87) and an electric machine (88) using the self-contained compressor (87) for boosting intake air into the intake manifold (30th ) drives includes. engine system (18, 112). claim 8 wherein the electrified air intensifier (85, 114) comprises an electric machine (126) mechanically coupled thereto to the turbocharger (124), a shaft (48) coupling the turbine (120) and the compressor (122), to drive, the turbocharger thus comprising an e-turbocharger (124) that boosts intake air into the intake manifold (30). engine system (18, 112). claim 8 wherein the controller (104) is configured to: identify when the engine load rate of change exceeds an engine load rate of change threshold; activate the electrified air amplifier (85, 114) when the engine load rate of change exceeds the engine load rate of change threshold; and upon activation of the electrified air amplifier (85, 114), controlling the governor (68, 118) to cease modification of exhaust gas flow through the turbine. engine system (18, 112). claim 1 , further comprising an exhaust gas recirculation (EGR) pump (76) operable to recirculate a portion of the exhaust gas discharged from the exhaust manifold (32) to the intake manifold (30), the EGR pump (76) in combination with the controller (104) that modifies the flow of exhaust gas through the turbine (40, 42, 120) is operable to further reduce NOx emissions from the engine system (18, 112). An engine system (18, 112) for a work vehicle (10), the engine system (18, 112) comprising: an engine (24) having one or more piston and cylinder assemblies (28) connected to an intake manifold (30) and communicating with an exhaust manifold (32); a turbocharger (36, 38, 116, 124, 128) having a turbine (40, 42, 120) connected to the exhaust manifold (32) and a compressor (44, 46, 122) connected to the Turbine (40, 42, 120) driven ben and in communication with the intake manifold (30); a governor (68, 118) configured to control exhaust gas flow through the turbine (40, 42, 120); and a controller (104) having a processor (104a) and memory (104b) architecture and operably connected to the controller (68, 118), the controller (104) being configured to: an engine load and an exhaust gas temperature to monitor during operation of the engine (24); determine whether the engine load and the exhaust gas temperature are below an engine load threshold and an exhaust gas temperature threshold, respectively, thereby indicating prohibited engine nitrogen oxide (NOx) emission levels; and if the engine load and the exhaust gas temperature are below the engine load threshold and the exhaust gas temperature threshold, controlling the controller (68, 118) to modify the exhaust gas flow through the turbine (40, 42, 120); wherein by modifying the flow of exhaust gas through the turbine (40, 42, 120), an amount of energy extracted from the exhaust gas by the turbine (40, 42, 120) is reduced and available to the compressor (44, 46, 122 ) supplied driving force is reduced, thereby reducing intake airflow supplied to the intake manifold (30) by the compressor (44, 46, 122). engine system (18, 112). Claim 13 wherein the turbocharger (36, 38, 116, 124, 128) comprises a variable geometry (VG) turbocharger (116), the turbine (120) having an adjustable aspect ratio that controls the amount of energy extracted from the exhaust gas is controlled when the exhaust gas flows therethrough, and wherein the controller (118) is configured to adjust the positioning of one or more components in the turbine (120) to adjust the aspect ratio. engine system (18, 112). Claim 13 Further comprising an electrified wastegate (66) operable between an open position and a closed position to cause the flow of exhaust gas to flow through the turbine (40, 42) or to bypass the turbine (40, 42), wherein the controller (68) is configured to actuate the electrified wastegate (66) between the open position and the closed position.

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